Today, the structure presents itself essentially as an arch skeleton: while the three semi-circular arches, made from local basalt, are still extant, the roadway and the fill have been removed to expose the top of the arch vaults.[2] Obliquely running embankments on both sides of the wadi force the water in the river bed under the bridge.[3]

At least two other Roman bridges over the Wadi Zeidi, the Kharaba Bridge and the one At-Tayyibeh, have survived to this day.[1]

1.
Roman roads
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They provided efficient means for the overland movement of armies, officials, and civilians, and the inland carriage of official communications and trade goods. Roman roads were of several kinds, ranging from local roads to broad, long-distance highways built to connect cities, major towns. These major roads were often stone-paved and metaled, cambered for drainage and they were laid along accurately surveyed courses, and some were cut through hills, or conducted over rivers and ravines on bridgework. Sections could be supported over marshy ground on rafted or piled foundations, at the peak of Romes development, no fewer than 29 great military highways radiated from the capital, and the late Empires 113 provinces were interconnected by 372 great roads. The whole comprised more than 400,000 kilometres of roads, in Gaul alone, no less than 21,000 kilometres of roadways are said to have been improved, and in Britain at least 4,000 kilometres. The courses of many Roman roads survived for millennia, some are overlaid by modern roads, livy mentions some of the most familiar roads near Rome, and the milestones on them, at times long before the first paved road—the Appian Way. Unless these allusions are just simple anachronisms, the referred to were probably at the time little more than levelled earthen tracks. Thus, the Via Gabina is mentioned in about 500 BC, the Via Latina in about 490 BC, the Via Nomentana, in 449 BC, the Via Labicana in 421 BC, and the Via Salaria in 361 BC. There is hardly a district to which we expect a Roman official to be sent, on service either civil or military. They reach the Wall in Britain, run along the Rhine, the Danube, and the Euphrates, and cover, as with a network, a road map of the empire reveals that it was generally laced with a dense network of prepared viae. Beyond its borders there were no paved roads, however, it can be supposed that footpaths, there were, for instance, some pre-Roman ancient trackways in Britain, such as the Ridgeway and the Icknield Way. For specific roads, see Roman road locations below, the Laws of the Twelve Tables, dated to about 450 BC, specified that a road shall be 8 Roman feet wide where straight and twice that width where curved. Actual practices varied from this standard, the Tables command Romans to build roads and give wayfarers the right to pass over private land where the road is in disrepair. Roman law defined the right to use a road as a servitus, the ius eundi established a claim to use an iter, or footpath, across private land, the ius agendi, an actus, or carriage track. A via combined both types of servitutes, provided it was of the width, which was determined by an arbiter. The default width was the latitudo legitima of 8 feet, Roman law and tradition forbade the use of vehicles in urban areas, except in certain cases. Married women and government officials on business could ride, the Lex Iulia Municipalis restricted commercial carts to night-time access in the city within the walls and within a mile outside the walls. Such roads led either to the sea, or to a town, or to a public river and these roads bear the names of their constructors

2.
As-Suwayda
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As-Suwayda, also spelled Sweida or Swaida, is a mainly Druze city located in southwestern Syria, close to the border with Jordan. It is the capital of As-Suwayda Governorate, one of Syrias 14 governorates, bordering Jordan in the South, the city is referred to by some as Little Venezuela due to the citys influx of affluent Syrian Venezuelan immigrants. The city has held by the government for the duration of the Syrian Civil War and has seen relatively little fighting. The inhabitants of the city are mainly Druze with a prominent Greek Orthodox Christians minority, the population of As-Suwayda Governorate is 313,231. The city was founded by the Nabataeans as Suada and it became known as Dionysias in the Hellenistic and Roman times, for Dionysus the god of wine - the city is situated in a famous ancient wine-producing region. Dionysias was a part of the Roman province of Arabia Petraea, Dionysus was worshipped in the same Nabatean temple dedicated for Dushara. This practice of associating the worship of local and Hellenic gods was common in Hellenistic Syria and this name remained in use during the Byzantine period, when the town was under the influence of Ghassanids, Dionysias then was a Diocese as a suffragan of Bosra. It was mentioned in the Synecdemus of Hierocles, after the Arab conquests it became a titular see. Yaqut al-Hamawi noted in the 1220s that As Suwaida was a village of the Hauran Province, in recent times Dionysias was firstly identified as Sweida by William Henry Waddington. Many archeological sites could be found in the old part of the city, Temple of Dionysus-Dushara, Saint Sergius Basilica, was built in the fifth century A. D. It has Byzantine architecture elements, with an abbey surrounding it, the basilica was dedicated to Saint Sergius. The arch of the church, the church itself is ruined. An arch is still standing there known locally as Al Mashnaqa with grape motif decorations, the amphitheatre, was recently discovered, south of the Agora. The city has many ancient reservoirs, towers and old Roman houses that are inhabited by locals. Many parts of the old city are still to be excavated like the Roman aqueduct, a reservoir. Map of the town, Google Maps

3.
Bosra
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According to the Syria Central Bureau of Statistics, Bosra had a population of 19,683 in the 2004 census. It is the center of the nahiyah of Bosra which consisted of nine localities with a collective population of 33,839 in 2004. Bosras inhabitants are predominantly Sunni Muslims, although the town has a small Shia Muslim community and it continued to be administratively important during the Islamic era, but became gradually less prominent during the Ottoman era. It also became a Latin Catholic titular see and the see of a Melkite Catholic Archeparchy. Today, it is a archaeological site and has been declared by UNESCO as a World Heritage Site. The settlement was first mentioned in the documents of Thutmose III, Bosra was the first Nabatean city in the 2nd century BC. The Nabatean Kingdom was conquered by Cornelius Palma, a general of Trajan, under the Roman Empire, Bosra was renamed Nova Trajana Bostra and was the residence of the legio III Cyrenaica. It was made capital of the Roman province of Arabia Petraea, the city flourished and became a major metropolis at the juncture of several trade routes, namely the Via Traiana Nova, a Roman road that connected Damascus to the Red Sea. It became an important center for production and during the reign of Emperor Phillip the Arab. The two Councils of Arabia were held at Bosra in 246 and 247 AD, by the Byzantine period which began in the 5th-century, Christianity became the dominant religion in Bosra. The city became a Metropolitan archbishops seat and a cathedral was built in the 6th-century. Bosra was conquered by the Sassanid Persians in the early 7th-century, Bosra played an important part in the early life of prophet Muhammad, as described in the entry for the Christian monk Bahira. The forces of the Rashidun Caliphate under general Khalid ibn Walid captured the city from the Byzantines in the Battle of Bosra in 634, throughout Islamic rule, Bosra would serve as the southernmost outpost of Damascus, its prosperity being mostly contingent on the political importance of that city. Bosra held additional significance as a center of the pilgrim caravan between Damascus and the Muslim holy cities of Mecca and Medina, the destinations of the hajj pilgrimage. Early Islamic rule did not alter the general architecture of Bosra, as Bosras inhabitants gradually converted to Islam the Roman-era holy sites were utilized for Muslim practices. In the 9th-century Yaqubi wrote that Bosra was the capital of the Hauran province, after the end of the Umayyad era in 750, major activity in Bosra ceased for around 300 years until the late 11th-century. In the last years of Fatimid rule, in 1068, a number of building projects were commissioned, with the advent of Seljuk rule in 1076, increasing focus was paid to Bosras defenses. In particular, the Roman theater was transformed into a fortress, with the coming to power of the Burid dynasty in Damascus, the general Kumushtakin was allotted the entire Hauran plain as a fief by the atabeg Tughtakin

4.
Syria
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Syrias capital and largest city is Damascus. Religious groups include Sunnis, Christians, Alawites, Druze, Mandeans, Shiites, Salafis, Sunni Arabs make up the largest religious group in Syria. Its capital Damascus and largest city Aleppo are among the oldest continuously inhabited cities in the world, in the Islamic era, Damascus was the seat of the Umayyad Caliphate and a provincial capital of the Mamluk Sultanate in Egypt. The post-independence period was tumultuous, and a number of military coups. In 1958, Syria entered a union with Egypt called the United Arab Republic. Syria was under Emergency Law from 1963 to 2011, effectively suspending most constitutional protections for citizens, Bashar al-Assad has been president since 2000 and was preceded by his father Hafez al-Assad, who was in office from 1970 to 2000. Mainstream modern academic opinion strongly favours the argument that the Greek word is related to the cognate Ἀσσυρία, Assyria, in the past, others believed that it was derived from Siryon, the name that the Sidonians gave to Mount Hermon. However, the discovery of the inscription in 2000 seems to support the theory that the term Syria derives from Assyria. The area designated by the word has changed over time, since approximately 10,000 BC, Syria was one of centers of Neolithic culture where agriculture and cattle breeding appeared for the first time in the world. The following Neolithic period is represented by houses of Mureybet culture. At the time of the pre-pottery Neolithic, people used vessels made of stone, gyps, finds of obsidian tools from Anatolia are evidences of early trade relations. Cities of Hamoukar and Emar played an important role during the late Neolithic, archaeologists have demonstrated that civilization in Syria was one of the most ancient on earth, perhaps preceded by only those of Mesopotamia. The earliest recorded indigenous civilisation in the region was the Kingdom of Ebla near present-day Idlib, gifts from Pharaohs, found during excavations, confirm Eblas contact with Egypt. One of the earliest written texts from Syria is an agreement between Vizier Ibrium of Ebla and an ambiguous kingdom called Abarsal c.2300 BC. The Northwest Semitic language of the Amorites is the earliest attested of the Canaanite languages, Mari reemerged during this period, and saw renewed prosperity until conquered by Hammurabi of Babylon. Ugarit also arose during this time, circa 1800 BC, close to modern Latakia, Ugaritic was a Semitic language loosely related to the Canaanite languages, and developed the Ugaritic alphabet. The Ugarites kingdom survived until its destruction at the hands of the marauding Indo-European Sea Peoples in the 12th century BC, Yamhad was described in the tablets of Mari as the mightiest state in the near east and as having more vassals than Hammurabi of Babylon. Yamhad imposed its authority over Alalakh, Qatna, the Hurrians states, the army of Yamhad campaigned as far away as Dēr on the border of Elam

5.
Arch bridge
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An arch bridge is a bridge with abutments at each end shaped as a curved arch. Arch bridges work by transferring the weight of the bridge and its loads partially into a horizontal thrust restrained by the abutments at either side, a viaduct may be made from a series of arches, although other more economical structures are typically used today. Possibly the oldest existing bridge is the Mycenaean Arkadiko bridge in Greece from about 1300 BC. The stone corbel arch bridge is used by the local populace. The well-preserved Hellenistic Eleutherna Bridge has a corbel arch. The 4th century BC Rhodes Footbridge rests on an early voussoir arch, a more complete survey by the Italian scholar Vittorio Galliazzo found 931 Roman bridges, mostly of stone, in as many as 26 different countries. Roman arch bridges were usually semicircular, although a number were segmental arch bridges, generally, Roman bridges featured wedge-shaped primary arch stones of the same in size and shape. The Romans built both single spans and lengthy multiple arch aqueducts, such as the Pont du Gard and Segovia Aqueduct. Their bridges featured from an early time onwards flood openings in the piers, e. g. in the Pons Fabricius in Rome, Roman engineers were the first and until the industrial revolution the only ones to construct bridges with concrete, which they called Opus caementicium. The outside was covered with brick or ashlar, as in the Alcántara bridge. The Romans also introduced segmental arch bridges into bridge construction, trajans bridge over the Danube featured open-spandrel segmental arches made of wood. This was to be the longest arch bridge for a thousand years both in terms of overall and individual span length, while the longest extant Roman bridge is the 790 m long Puente Romano at Mérida. The late Roman Karamagara Bridge in Cappadocia may represent the earliest surviving bridge featuring a pointed arch, in medieval Europe, bridge builders improved on the Roman structures by using narrower piers, thinner arch barrels and lower span-rise ratios on bridges. Gothic pointed arches were introduced, reducing lateral thrust. The 14th century in particular saw bridge building reaching new heights, the bridge at Trezzo sullAdda, destroyed in the 15th century, even featured a span length of 72 m, not matched until 1796. Constructions such as the acclaimed Florentine segmental arch bridge Ponte Vecchio combined sound engineering with aesthetical appeal, the three elegant arches of the Renaissance Ponte Santa Trinita constitute the oldest elliptic arch bridge worldwide. In China, the oldest existing bridge is the Zhaozhou Bridge of 605 AD. The Zhaozhou Bridge, with a length of 167 feet and span of 123 feet, is the worlds first wholly stone open-spandrel segmental arch bridge, Bridges with perforated spandrels can be found worldwide, such as in China

6.
Basalt
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Basalt is a common extrusive igneous rock formed from the rapid cooling of basaltic lava exposed at or very near the surface of a planet or moon. Flood basalt describes the formation in a series of basalt flows. By definition, basalt is an igneous rock with generally 45-55% silica and less than 10% feldspathoid by volume. Basalt commonly features a very fine-grained or glassy matrix interspersed with visible mineral grains, the average density is 3.0 gm/cm3. Basalt is defined by its content and texture, and physical descriptions without mineralogical context may be unreliable in some circumstances. Basalt is usually grey to black in colour, but rapidly weathers to brown or rust-red due to oxidation of its mafic minerals into hematite, although usually characterized as dark, basaltic rocks exhibit a wide range of shading due to regional geochemical processes. Due to weathering or high concentrations of plagioclase, some basalts can be quite light-coloured and these phenocrysts usually are of olivine or a calcium-rich plagioclase, which have the highest melting temperatures of the typical minerals that can crystallize from the melt. Basalt with a texture is called vesicular basalt, when the bulk of the rock is mostly solid. Gabbro is often marketed commercially as black granite and these ultramafic volcanic rocks, with silica contents below 45% are usually classified as komatiites. Agricola applied basalt to the black rock of the Schloßberg at Stolpen. Tholeiitic basalt is relatively rich in silica and poor in sodium, included in this category are most basalts of the ocean floor, most large oceanic islands, and continental flood basalts such as the Columbia River Plateau. Basalt rocks are in some cases classified after their content in High-Ti and Low-Ti varieties. High-Ti and Low-Ti basalts have been distinguished in the Paraná and Etendeka traps and it has greater than 17% alumina and is intermediate in composition between tholeiite and alkali basalt, the relatively alumina-rich composition is based on rocks without phenocrysts of plagioclase. Alkali basalt is relatively poor in silica and rich in sodium and it is silica-undersaturated and may contain feldspathoids, alkali feldspar and phlogopite. Boninite is a form of basalt that is erupted generally in back-arc basins. Ocean island basalt Lunar basalt On Earth, most basalt magmas have formed by melting of the mantle. Basalt commonly erupts on Io, the third largest moon of Jupiter, and has formed on the Moon, Mars, Venus. The crustal portions of oceanic tectonic plates are composed predominantly of basalt, produced from upwelling mantle below, the mineralogy of basalt is characterized by a preponderance of calcic plagioclase feldspar and pyroxene

7.
Ancient history
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Ancient history is the aggregate of past events from the beginning of recorded human history and extending as far as the Early Middle Ages or the Postclassical Era. The span of recorded history is roughly 5,000 years, beginning with Sumerian Cuneiform script, the term classical antiquity is often used to refer to history in the Old World from the beginning of recorded Greek history in 776 BC. This roughly coincides with the date of the founding of Rome in 753 BC, the beginning of the history of ancient Rome. In India, ancient history includes the period of the Middle Kingdoms, and, in China. Historians have two major avenues which they take to better understand the ancient world, archaeology and the study of source texts, primary sources are those sources closest to the origin of the information or idea under study. Primary sources have been distinguished from secondary sources, which cite, comment on. Archaeology is the excavation and study of artefacts in an effort to interpret, archaeologists excavate the ruins of ancient cities looking for clues as to how the people of the time period lived. The study of the ancient cities of Harappa, Mohenjo-daro, the city of Pompeii, an ancient Roman city preserved by the eruption of a volcano in AD79. Its state of preservation is so great that it is a window into Roman culture and provided insight into the cultures of the Etruscans. The Terracotta Army, the mausoleum of the First Qin Emperor in ancient China, the discovery of Knossos by Minos Kalokairinos and Sir Arthur Evans. The discovery of Troy by Heinrich Schliemann, most of what is known of the ancient world comes from the accounts of antiquitys own historians. Although it is important to take account the bias of each ancient author. Some of the more notable ancient writers include Herodotus, Thucydides, Arrian, Plutarch, Polybius, Sima Qian, Sallust, Livy, Josephus, Suetonius, furthermore, the reliability of the information obtained from these surviving records must be considered. Few people were capable of writing histories, as literacy was not widespread in almost any culture until long after the end of ancient history, the earliest known systematic historical thought emerged in ancient Greece, beginning with Herodotus of Halicarnassus. He was also the first to distinguish between cause and immediate origins of an event, the Roman Empire was one of the ancient worlds most literate cultures, but many works by its most widely read historians are lost. Indeed, only a minority of the work of any major Roman historian has survived, prehistory is the period before written history. The early human migrations in the Lower Paleolithic saw Homo erectus spread across Eurasia 1.8 million years ago, the controlled use of fire occurred 800,000 years ago in the Middle Paleolithic. 250,000 years ago, Homo sapiens emerged in Africa, 60–70,000 years ago, Homo sapiens migrated out of Africa along a coastal route to South and Southeast Asia and reached Australia

8.
Ancient Roman architecture
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Ancient Roman architecture adopted the external language of classical Greek architecture for the purposes of the ancient Romans, but differed from Greek buildings, becoming a new architectural style. The two styles are considered one body of classical architecture. Roman architecture flourished in the Roman Republic and even more so under the Empire and it used new materials, particularly concrete, and newer technologies such as the arch and the dome to make buildings that were typically strong and well-engineered. Large numbers remain in some form across the empire, sometimes complete, Roman Architecture covers the period from the establishment of the Roman Republic in 509 BC to about the 4th century AD, after which it becomes reclassified as Late Antique or Byzantine architecture. Almost no substantial examples survive from before about 100 BC, and most of the major survivals are from the later empire, after about 100 AD. They moved from trabeated construction mostly based on columns and lintels to one based on walls, punctuated by arches. The classical orders now became largely decorative rather than structural, except in colonnades, however, they did not feel entirely restricted by Greek aesthetic concerns, and treated the orders with considerable freedom. Innovation started in the 3rd or 2nd century BC with the development of Roman concrete as a readily available adjunct to, or substitute for, stone, more daring buildings soon followed, with great pillars supporting broad arches and domes. The freedom of concrete also inspired the colonnade screen, a row of decorative columns in front of a load-bearing wall. In smaller-scale architecture, concretes strength freed the floor plan from rectangular cells to a more free-flowing environment, factors such as wealth and high population densities in cities forced the ancient Romans to discover new architectural solutions of their own. The use of vaults and arches, together with a knowledge of building materials. Examples include the aqueducts of Rome, the Baths of Diocletian and the Baths of Caracalla and these were reproduced at a smaller scale in most important towns and cities in the Empire. Some surviving structures are almost complete, such as the walls of Lugo in Hispania Tarraconensis. The administrative structure and wealth of the empire made possible very large even in locations remote from the main centres, as did the use of slave labour. Especially under the empire, architecture often served a function, demonstrating the power of the Roman state in general. The influence is evident in many ways, for example, in the introduction and use of the Triclinium in Roman villas as a place, Roman builders employed Greeks in many capacities, especially in the great boom in construction in the early Empire. The Roman Architectural Revolution, also known as the Concrete Revolution, was the use in Roman architecture of the previously little-used architectural forms of the arch, vault. For the first time in history, their potential was fully exploited in the construction of a range of civil engineering structures, public buildings

9.
Pont Ambroix
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The Pont Ambroix or Pont dAmbrussum was a 1st-century BC Roman bridge in the south of France which was part of the Via Domitia. It crossed the Vidourle at Ambrussum, between todays Gallargues-le-Montueux in the Gard department and Villetelle in the Hérault department, in the High Middle Ages, a chapel devoted to St Mary was added to the structure. Today, only one of the original eleven arches remains in the middle of the river, the bridge was sketched by Anne Rulman in 1620 and the drawing shows only four arches. A1839 lithograph and a painting by Gustave Courbet show two arches, the Vidourlades are violent floods or crues on the Vidourle, During a crue, the water flow increases from a minimum of 3 m3/s to over 3000 m3/s. Floods were recorded 8 October 1723, the floods of 18 November 1745 reduced the bridge from four arches to three. Further major floods occurred 6 October 1812,21 October 1891,21 September 1907, the floods of 7 September 1933 reduced the bridge from two arches to the one we see today. The bridge is a Mérimée list National Monument No, the oppidum is a Mérimée list National Monument No. PA00103760 O’Connor, Colin, Roman Bridges, Cambridge University Press, p

10.
Pont Flavien
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The Pont Flavien is a Roman bridge across the River Touloubre in Saint-Chamas, Bouches-du-Rhône department, southern France. The single-arch crossing, which was built from limestone, was on a Roman road - the Via Julia Augusta - between Placentia, Italy and Arles, the bridge probably replaced an earlier wooden structure on the same site. It measures 21.4 metres long by 6.2 metres wide, the two arches at either end, each standing 7 metres high with a single wide bay, are constructed of the same local stone as the bridge and are broader than they are tall. At the corners of the arches are fluted Corinthian pilasters at the top of which are carved eagles, lucius Donnius Flavos was evidently a figure of some importance and probably owned land in the vicinity of the bridge. He was a Romanised Gaul who is likely to have been an aristocrat of the Avatici and he was probably also a significant player in the affairs of the nearby city of Arelate, as he served the imperial cult, most likely in one of the citys temples. He may have built his mausoleum nearby, though its location remains unknown, as the inscription indicates, the bridge was constructed at Flavos instigation following his death. Its stylistic elements are typical of funerary monuments, the frieze of the arches decorated with a wave pattern symbolises the constant rebirth of life. The combination of arches and a bridge may have intended to symbolise the passage of life. Because the Pont Flavien was a monument it did not have the triumphal imagery normally associated with Roman arches and does not bear any portrait of Flavos. He would most likely have been depicted in figure at his tomb but this, in the 20s BC, Marcus Vipsanius Agrippa carried out a programme of road building in Provence on behalf of the Emperor Augustus, constructing the Via Julia Augusta. This would have given Flavos an opportunity to make his mark in a visible way, proclaiming his dedication to Roman values. Considering also the date of the stylistic elements, the Pont Flavien was most likely built some time between 20 and 10 BC. The bridge was used until as late as the latter part of the 20th century. It has been resurfaced to prevent the collapse of the bridge. The western arch has collapsed at least twice, the first time was in the 18th century and it was rebuilt in 1763 by Jean Chastel, who also restored the sculptures. The second collapse was during the Second World War, when the arch was first damaged when a German tank collided with it and it was rebuilt in 1949 and some years later a modern bridge was built 50 metres to the south to bypass it. The Pont Flavien is now reserved for use only. In 1977, prior to the landscaping of the surrounding area, list of Roman bridges Roman architecture Roman engineering Media related to Pont Flavien at Wikimedia Commons Pont Flavien at Structurae Pont Flavien

11.
Pont du Gard
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The Pont du Gard is an ancient Roman aqueduct that crosses the Gardon River near the town of Vers-Pont-du-Gard in southern France. The Pont du Gard is the highest of all elevated Roman aqueducts and it was added to UNESCOs list of World Heritage Sites in 1985 because of its historical importance. The aqueduct bridge is part of the Nîmes aqueduct, a 50-kilometre system built in the first century AD to carry water from a spring at Uzès to the Roman colony of Nemausus. Because of the terrain between the two points, the mostly underground aqueduct followed a long, winding route that called for a bridge across the gorge of the Gardon River. The bridge has three tiers of arches, stands 48.8 m high, and descends a mere 2, the aqueduct formerly carried an estimated 200,000 m3 of water a day to the fountains, baths and homes of the citizens of Nîmes. After the Roman Empire collapsed and the fell into disuse. It attracted increasing attention starting in the 18th century, and became an important tourist destination, today it is one of Frances most popular tourist attractions, and has attracted the attention of a succession of literary and artistic visitors. The location of Nemausus was somewhat inconvenient when it came to providing a water supply, the only real alternative was to look to the north and in particular to the area around Ucetia, where there are natural springs. The Nîmes aqueduct was built to water from the springs of the Fontaine dEure near Uzès to the castellum divisorum in Nemausus. From there, it was distributed to fountains, baths and private homes around the city, the straight-line distance between the two is only about 20 km but the aqueduct takes a winding route measuring around 50 km. This was necessary to circumvent the southernmost foothills of the Massif Central and they are difficult to cross, as they are covered in dense vegetation and garrigue and indented by deep valleys. It was impractical for the Romans to attempt to tunnel through the hills, a roughly V-shaped course around the eastern end of the Garrigues de Nîmes was therefore the only practical way of transporting the water from the spring to the city. The aqueducts average gradient is only 1 in 3,000 and it varies widely along its course, but is as little as 1 in 20,000 in some sections. The Pont du Gard itself descends 2.5 cm in 456 m, the average gradient between the start and end of the aqueduct is far shallower than was usual for Roman aqueducts – only about a tenth of the average gradient of some of the aqueducts in Rome. This height limit governed the profile and gradients of the entire aqueduct, the gradient profile before the Pont du Gard is relatively steep, descending at 0.67 metres per kilometre, but thereafter it descends by only 6 metres over the remaining 25 kilometres. It is estimated that the aqueduct supplied the city with around 200,000 cubic metres of water a day that took nearly 27 hours to flow from the source to the city. The water arrived in the castellum divisorum at Nîmes – an open, shallow and it would have been surrounded by a balustrade within some sort of enclosure, probably under some kind of small but elaborate pavilion. When it was excavated, traces of a roof, Corinthian columns

12.
Pont Julien
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The Pont Julien is a Roman stone arch bridge over the Calavon river, in the south-east of France, dating from 3 BC. The supporting columns are notable for openings to allow floodwater to pass through and it is located in the territory of the commune of Bonnieux, north of the village of the same name, and 8 km west of Apt. Originally, it was built on the Via Domitia, an important Roman road which connected Italy to the Roman territories in France and it was used for car traffic until 2005, when a replacement bridge was built to preserve it from wear and tear. This amounts to approximately 2000 years of uninterrupted use, list of Roman bridges Roman architecture Roman engineering Murati, Philippe. O’Connor, Colin, Roman Bridges, Cambridge University Press, pp. 96f, ISBN 0-521-39326-4 Media related to Pont Julien at Wikimedia Commons Pont Julien at Structurae Traianus – Technical investigation of Roman public works